Hoeke, R., Brainard, R. E., Moffitt, R., Merrifield, M.

The role of oceanographic conditions and reef morphology in the 2002 coral bleaching event in the Northwestern Hawaiian Islands

2006

Atoll Research Bulletin

543

489-503

"Researchers on two research cruises to the Northwestern Hawaiian Islands (NWHI) in September 2002 recorded widespread massive coral bleaching, particularly at Kure, Midway, and Pearl and Hermes atolls at the northern end of the Hawaiian Archipelago. While details of the coral bleaching and biological impacts are presented by Kenyon et al. (in review), this work is focused on the contributions of broad-scale meteorological and oceanographic conditions, as well as the local effects of reef morphology, to the severity and distribution of the observed coral bleaching. Anomalously high regional sea surface temperature (SST), identified as the primary proximate factor in the bleaching event, was related to a band of quiescent winds and high insolation intersecting the northern end of the Hawaiian Archipelago. These conditions were in turn related to a variable ridge of high atmospheric surface pressure present both immediately preceding and during the event. Atoll/reef morphology and circulation patterns inferred from in situ observations are used to explain localized elevation of SST within the three northernmost atolls which increased the severity of bleaching within lagoon and backreef habitats. A method of predicting overall differences in bleaching between adjacent reef groups in the absence of detailed in situ temperature data is presented. This method relies on regression of lagoon and backreef volumes and satellite SST to describe observed coral bleaching."

FY2004 CRCP Project ID 1220; Project Title: Legal Analysis for Puerto Ricos Marine Natural Reserves; Principal Investigator: Rusty Brainard